Method for application of a wax coating to cartons



J. A. ZINN, JR

July 20, 1954 METHOD FOR APPLICATION OF A WAX comma TO CARTONS FiledFeb. 24, 1950 ll Sheets-Sheet l INVENTOR.

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July 20, 1954 Filed Feb. 24, 1950 J. A. ZINN, JR

METHOD FOR APPLICATION OF A WAX COATING TO CARTONS 11 Sheets-Sheet gHVVENTDR.

J. A. ZINN, JR

July 20, 1954 11 Sheets-Shea 3 Filed Feb. 24, 1950 w m m M J J. A. ZINN,JR

July 20, 1954 METHOD FOR APPLICATION OF A WAX COATING TO CARTONS llSheets-Sheet 4 Filed Feb. 24, 1950 IN V EN TOR.

J. A. ZINN, JR

July 20, 1954 METHOD FOR APPLICATION OF A WAX COATING TO CARTONS llSheets-Sheet 5 Filed Feb. 24, 1950- &

INVENTOR.

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July 20, 1954 J. A. ZINN, JR

METHOD FOR APPLICATION OF A WAX COATING TO CARTONS 11 Sheets- Sheet 6Filed Feb. 24, 1950 INVENTOR.

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, METHOD FOR APPLICATION A WAX COATING TO CARTONS Filed Feb. 24, 1950 11Sheets-Sheet 7 THAI I"! l;

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IN V EN TOR.

July 20, 1954 METHOD FOR APPLICATION OF A WAX COATING TO CARTONS FiledFeb. 24, 1950 J. A. ZINN, JR

11 Sheets-Sheet 8 July 20, 1954,

J. A. ZINN, JR

METHOD FOR APPLICATION OF A WAX COATING TO CARTONS ll Sheets-Sheet 9 I wI] Filed Feb. 24, 1950 INVENTOR. Jaizw (Z Zu Z/Z/ Jt,

J. A. ZlNN, JR

July'ZO, 1954 METHOD FOR APPLICATION OF A WAX COATING T0 CARTONS FiledFeb. 24, 1950 ll Sheets-Sheet 10 wmm J. A. ZINN, JR

July 20, 1954 METHOD FOR APPLICATION OF A WAX COATING TO CARTONS llSheets-Sheet 11 Filed Feb. 24, 1950n1'1!rtilIIIIIIIIIlllllllilllllllllIlIIllI-rl'ffll will!!! rlfllll!!!Patented July 20, 1954 UNITED STATES FATENT OFFICE METHOD FORAPPLICATION OF A WAX COATING TO GARTONS 2 Glaims.

This invention relates to a new and improved method for the applicationof a wax coating to formed cartons and for the cooling and hardening ofsaid coatings. More particularly the invention relates to a method ofthis character which involves continuous operation and is suitable foruse in direct association with a carton forming machine which is alsocontinuously operated.

Apparatus has heretofore been in use for forming cartons of cardboard orthe like from fiat blanks and other apparatus has been in use forpassing the formed blanks through a heated bath of wax, such asparaffine or similar material. Such apparatus has, however, beenintermittent in operation with a step by step movement of the cartonmachine and waxer, the cycle of operation being stopped for loading theapparatus and delivering the product therefrom. The stop and go forms ofapparatus taking a single carton at a time are comparatively low inproduction since they cannot be operated efliciently at high speeds dueto shock and wear caused by repeated stops and starts. To give largerproduction, some stop and go machines take a plurality of cartons inparallel, but these machines generally require longer stops for loadingand are therefore slow and, in addition, are bulky requiring largeheating, wax bath and cooling facilities which are costly.

It is an object of the present invention to provide a method forapplying wax to cartons and for cooling the applied wax, which method iscapable of being carried out by continuous operation at relatively highspeeds.

It is a further object to provide such a method which will apply andcool a uniform and smooth layer of wax.

It is an additional object to provide a method by which the time ofimmersion of the cartons in the bath may be accurately controlled forvariable speeds at which cartons are blown in or otherwise introducedinto the waxer.

It is also an object to provide a method by which the cartons aredrained of excess wax in a heated chamber and thereafter transferred toa cooling chamber for rapid and continuous cooling of all surface areas.

It is another object to provide a method by which cartons having an openend and a closed end are introduced into the wax bath with the closedend lower than the open end and are removed from the bath with the openend lower than the closed end.

It is a further object to provide a method which may be carried out byapparatus including endless conveyors for the cartons, the movement andthe relative location of the conveyors being adjustable to provideefficient loading, unloading and transfer operations while all elementsare in continuous motion.

It is an additional object to provide a method in which the wax feed tothe wax bath and the wax level in the bath are automatically controlled.

It is an additional object to provide a method which is efficient andrapid in operation and adapted for commercial use.

Other and further objects will appear as the description proceeds.

Certain preferred embodiments of one form I of apparatus suitable forcarrying out the method of the invention are shown in the accompanyingdrawings, in which- Figure 1 is a plan view showing a waxing machine andcooler associated with a suitable gluerfeeder and package maker;

Figure 2 is a front elevation of the waxing machine and cooler shown inFigure 1;

Figure 3 is a partly broken away section taken on line 3--3 of Figure 1;

Figure 4 is a vertical section taken on line 4-5 of Figure 1;

Figure 5 is a transverse vertical section taken on line 5-5 of Figure 4;

Figure 6 is a fragmentary face view of the drive sprocket of Figure 5;

Figure 7 is a fragmentary elevation, on an enlarged scale, showing thereceiving chute for the waxer;

Figure 8 is a plan View of the chute construction shown in Figure 7taken on line 8-8 of Figure '7;

Figure 9 is a fragmentary view taken on line 9-9 of Figure '7;

Figure 10 is a fragmentary view, on an enlarged scale, showing one ofthe carton receiving and holding baskets in the waxer;

Figure 11 is a plan view of the construction shown in Figure 10;

Figure 12 is a fragmentary vertical section showing the mechanism fortransferring cartons from the waxer to the cooler;

Figure 13 is a fragmentary elevation showing the heating coils of Figure12;

Figure 14 is a side elevation of the outside chute for receiving cartonsfrom the carton maker;

Figure 15 is a plan view of the chute of Figure 14;

Figure 16 is a vertical longitudinal section through the cooler taken online iii-i of Figure l; and

Figure 17 is a horizontal section of the cooler taken on line illl ofFigure 13.

Referring first to Figure l, the gluer and feeder 2! indicated at theleft of the figure may take the form of construction shown in theco-pend ing application of Julius A. Zinn, Jr, Serial No. 102,345, filedJune 30, 1949, now Patent No. 2,651,283, issued September 8, 1953. Thetransfer conveyor 23 may take the form of the con veyor shown in thepatent to Julius A. Zinn, and Michael J. Wilson, No. 2,480,177, issuedAugust 3, N49. The carton or package maker may take the form of thepackage maker of the co-pending application of Julius A. Zinn, J12,Serial No. 752,364, filed June i, 1947, now Patent No. 2,5 3,899, issuedApril 3, 1951.

The carton or package maker of the continuous rotary type and completedcartons are discharged by compressed air from the mandrels on the cartonor package maker into the transfer chute 2% through which they pass intothe waxing machine 25. As will be described hereafter in detail, thefully formed cartons are carried in baskets in the waxing machine in atortuous path through a bath of wax, such as parafnne, remaining in thebath for a predetermined period or" time at a predetermined temperature.After leaving the bath, the cartons tilted so as to drain excess wax andare then transferred to a conveyor operating in the cooler This conveyor carries the formed and waxed cartons through the cooler in atortuous path so as to allow them a predetermined period in a coolatmosphere at a predetermined temperature and to cool the cartons at aspeed such that the whole system of apparatus may be operated at themaximum eiiective speed of the package maker From the cooler thecompleted cartons are discharged to any suitable apparatus, not shown.This apparatus may take the form of filling and closing machines ormerely apparatus for stacking and boxing the finished cartons forshipment.

Referring next to Figure 5, the cartons pass through the chute 25 intothe feed control assemly whicis shown in detail in Figures 7, 8 and 9.From the lower end of this assembly at the cartons pass individuallyinto baskets S l which are supported at their opposite ends upon chainsas and 38. As shown in Figure 5, these chains 35 and 323 pass over uppersprockets 4e and ill carried on shaft l2 supported in the journals t3and i The shaft 22 is driven from a suitable source of power through thesprocket drive wheel 65. This wheel is adjustably mounted on hub is bybolts ii fitting slots 58, as shown in Figure 6. The relative locationof the baskets 3t and the speed of movement of the conveyor must beaccurately synchronized with the feed from the carton maker or otherfeed apparatus. At the lower end of the vertical run shown in Figure 5,the chains 36 and 33 pass over the lower sprocket wheels it and 5c.

Referring to both Figures 4 and 5, it will be apparent that lowersprocket as is mounted on an axis above the axis of the similar sprocket559. The lower longitudinal passes of chains 35 and 38 then pass overthe sprockets 5i and 52 respectively, which sprockets have the sprocket52 on a higher axis than the sprocket 5 I. From sprockets Eli and 52,the chains 3t and 38 have a reverse, approximately horizontal run tosprockets 53 and i 55, the sprocket 5 i rotating about a higher axisthan sprocket 53. From sprockets 53 and 54, the chains 36 and 33 have agenerally horizontal run in the reverse direction to the sprockets 55and 55 which are offset laterally from which they return in a generallyhorizontal run to sprockets it and M.

It will be apparent, from considering the elevation of the baskets t lshown in Figures 5 and 10, that during their vertical run past the end33 of the fixed assembly 32 the baskets are tilted at an angle ofapproximately 30 to the horizontal so that their cpenable upper end 5&passes as a substantial continuation of the feed or admission assembly32, as shown in Figure 5. Because of the relationship of the axes ofsprockets 4s and 53, when the containers B l pass around sprockets 29and to their lower run as shown in Figure l, the containers 3d arefurther tilted so that their lower closed ends enter the bath below andin advance of the open end. Since the open end of the cartons is towardsthe cpcnable end of the baskets 3Q, this movement assures that the lowerclosed ends of the cartons enter the wax bath first and no air istrapped in the cartons. As the baskets 3t reach the lower runs of chains36 and at, the lead of the lower ends or" the baskets is lost and thebaske travel laterally. The lead of the basket end carrying the closedend of the carton is regained as the conveyor rounds sprockets Thecrossed lower runs of 28 and 3 3, as shown in Figure l, vary thevertical tilt of the cartons to insure lull contac with the wax.

In order to drain the wax from the cartons, it necessary to tilt thecartons to bring their open ends lower than their closed ends, and thisis accomplished by having the chain 38 connected to the bottoms ofcontainers pass over the sprocket pulley 52 while chain 35 connected tothe upper end of containers til passes over the lower sprocket pulley 5After leaving the pulleys 5i and the draining positioning of thecontainers El i and cartons therein is maintained by having the chain3-? extend over the pulley it while the chain extends over the somewhatlower pulley 53. The two chains again become parallel under the pair ofpulleys and 56 which are in the same horizontal plane. The lateraloffset of pulleys t5 and is such as to make the total length of the twochains and 38 the same. The adjusting means serve to take up slack inchain 33 by moving pulley to the right or left and similar means areprovided in connection with pulley 55. Similar adjusting means lid and65 are located on the supports for the sprockets 5t and 52, and the sametype of adjusting means are provided for the rear sprockets lt and 5 I.It will be understood that the various adjustments must be coordinatedto provide equal lengths for the two chains and 38. Such adjustmentsallow modification of the angle of lead of one end of the baskets 34over the other end at different points along the conveyor.

An idler pulley 82 is located near sprocket 56 to insure a horizontalrun of chain 33 for a short stretch during which the cartons aredischarged from the baskets 35 into the transfer mechantsin shown inFigures 12 and 13. A similar supporting idler pulley 53 holds up chainso that it will have a horizontal run in the same plane as chain 38 atthis discharge point. Drip pans 5i and 53 are located under this upperrun of the conveyor to prevent wax dripping onto cartons in the lowerrun. From pulleys 55 and 56, the two chains pass in a parallel run overidler pulleys 6| back to the pulleys 4| and 40.

Referring to Figures 5, 14 and 15, the feed chute 26 is shown with itsside walls provided with outwardly pressed portions '55 providing asubstantial clearance for the cartons, which are blown bottom foremostinto the chute from the carton machine or package maker 24, shown inFigure 1. These portions .15 provide space for passage of air trappedahead of the cartons and facilitate their movement. The sides it of thechute 26 may be formed from sheets of transparent plastic so that thefeed of the cartons may be visible. A hinged door I! is provided at thebottom of the chute and this may be opened to remove any cartons whichbecome jammed in the chute. It has been found that this door I? and itsopening serve to eject automatically carton whose bottoms are not fullysealed or which become unsealed due to ihe air blast used to blow themfrom the carton machine mandrels through the chute 263 to the waxer. Acarton with a fully closed bottom is blown at high speed through thechute 2E and is deflected in a downward curve by contact with the innerface of the curved upper surface of the chute above the door 7?. If thecarton bottom flaps are not properly stuck together and the bottom isopened or partially opened by the air blast, the carton is not moved sorapidly by the blast and tends to slide along the bottom of chute 26 anddrop through the opening if door I? is left open. The bottom flaps whichare unstuck also may create an air drag and drag against the chutewalls, which also slows its speed and helps cause it to drop out of thedoor opening. The chute is hingedly supported at I8 to the frame of thewaxer so that it may be swung upward to clear the space between thepackage maker 24 and the Waxer 28 to provide clearance for repair andadjustment vided with an adjustable screw 86 bearing against the lug 8'!which is secured to the upper edge of the assembly 32. The tensionspring 88 has one end secured to the member 84 and the other end securedto a pin 89 extending from the side wall of the assembly 32. silientfingers 83 are held down by the tension of the spring, and the distancewhich they extend into the path of the cartons passing into the assembly32 is controlled by the adjustment of the screw 86.

A lateral guide spring BI is secured to the inner face of the side ofthe assembly 32 and has a transverse portion 92 and a reversely bent end93 extending through a slot 94 in the side member. A bottom gate 96 isconnected to the cross pivot member 9'! and closes the lower portion ofthe inner or discharge end of the assembly 32. The spring 9i has a lightspring action which urges the cartons against the rear side 95 of theassembly to insure proper delivery to the conveyor basket 34. It has theadditional important function that the transverse portion 92 stops anyrebound of a carton from the conveyor basket 34 and prevents arebounding carton from jam.- ming the gate 96 and stopping the machine.

It will be apparent that the re- The arm 98 is rigidly connected to thepivot member 91 and an upper arm I00 is also rigidly connected to thispivot member 91. The tension spring IIJI is connected at one end to theupper end of the arm Inc and at its other end to a pin I03 extendingfrom the side wall of the assembly 32. The gate 35 is provided with across member Ill l which engages the under side of the side wall of theassembly 32 to limit swinging movement of the gate in thecounterclockwise direction about its pivot member 91.

The arm 98 is connected by link I06 to the inwardly threaded member I6!into which is threaded an end of the switch control plunger H13. Thisplunger I08 is looked in adjusted position in member It! by nut I09. Theouter end of the member I88 has a conical taper, as shown at HI, and islocated between a pair of plungers H3 which, as best shown in Figure 9,operate switches H5. These switches II5 are located in control circuitsfor operation of the apparatus and are normally closed. It will beapparent that any jam of cartons occurring in the feed assembly 32 orcarton with open bottom flaps will depress the guide 96, thus swingingthe arm 98 in the clockwise direction and through link ltd, member it?and plunger I08, forcing the tapered end I I i of that plunger to theleft, as seen in Figure 7, thus forcing the switch control plungers H3inwardly into the switches and opening the circuits controlled by theseswitches. This will automatically stop the apparatus and permit clearingany jam occurring at this point.

t will be understood that it is desirable to continue movement of theconveyor and associated parts in the waxer so as to properly time thewaxing of cartons already in that machine and, therefore, these switchesi I 5 normally control circuits which have to do with the operation ofthe carton machine 24 and its feed apparatus or any other externalcarton feed apparatus so as to prevent the further feed of formedcartons until the jam has been cleared in the feed to the Waxer.

From the feed assembly 32, the formed cartons are discharged into thebaskets 34 carried by the conveyor chains 36 and 38. These baskets 34are shown in detail in Figures 10 and 11. The containers each comprise afixed lower side Wall Ill and fixed inner vertical wall i I9, thesewalls being formed at right angles to each other. The vertical walls H9have extending therefrom the support lug I2I and the aligned supportframe I22. The support rod in is rigidly connected to the yoke 625 whichis pivotally connected by pin I26 to the transverse yoke I2 I, as shownat the left of Figures 10 and 11. This yoke I2'I is pivotally supportedon the pin I23 which is carried in the stirrup 533, the latter beingrigidly secured to a link of the conveyor chain 36.

The rod I24 slides freely through lug I2I and its free end also slidesfreely in the aligned support frame I22. The other end of the frame I22is provided with a bifurcated portion I32 connected by pivot pin I33 toyoke I34. This yoke I3t is pivotally connected by pin I36 to the stirrupI38 which is rigidly connected to a link of the conveyor chain 38.

The lower side wall Ill and rear wall IIQ of the basket are rigidlyconnected by the fixed bottom wall I40. As shown in Figure 10, thisbottom wall is provided with conical projections M2 which keep thebottom of the carton, indicated in broken lines at I44, from engagingthe full area of the bottom I413. The upper edge of the bottom I46 isprovided with bearings I46 and I 41 in which are fitted the pivot pinI48. The cover carrying arm I 19 is secured to pin I48 and rotatestherewith. The cover actuating arm [58 is also secured to the pin Idaand rotates with that pin. This arm I 56 carries the cam engaging rollerIEI and, at its opposite end, has the lug I52 extending under theadjusting screw I53 carried by the bearing member I 56. The spring I54is coiled about the pivot I43 and has one end I55. engaging the upperface of the arm I49 while its other end I55 is held by the bearing I46.The spring I54 thus holds the arm I49 downwardly with the lug I52engaging the under face of screw I53.

The cover I? is connected to the cover carrying arm M9 by means of thepivot pin I58. The underside of this cover is engaged by the spring I59,one end of which is fitted in a slot in the cover carrying member I49,as shown at Ito in Figure 10. This spring I59 yieldingly holds the outerend of the cover I51 upwardly so that the carton may freely enter thebasket when the cover is open. The rear portion of the basket cover IE'Iis tilted upwardly as it engages the carton IM when the cover is closedby spring I54. The free end of spring I59 also engages the carton. Thecover ISI has the downturned outer end ifii adapted to prevent thecarton from moving outwardly of the container 3 3 to the left, as shownin Figures and 11. The cover member I51 also has the downturned lateraledge I63 which prevents lateral movement of the carton in the directionaway from the wall I is. It will be noted that the member I63 extendsonly over a small portion of the side of the carton. By thisconstruction the carton is positively held in place in the basket by theportions as: and I63 of the cover I5? and is lightly held by spring I59.The strength of spring lit and the relationship of the parts is suchthat there is no tendency to crush the carton, the cover I57 being freeto take a position parallel to the adjacent carton surface.

As shown in Figure 4, the waxer is provided at its lower left side withthe guide members I55 which are adapted to fit laterally of the portionI83 of the cover member I5? and engage the cartons to guide and hold thecartons from coming out as the baskets 3 pass around the lower pulleys29 and 523 into the wax bath. Similar guides I538 are provided for thesame purpose at the right side to guide and hold the cartons as theyleave the bath. As shown in Figure 5, the apparatus is provided with acam member It? which has an inturned upper end I68. In the downwardmovement of the conveyor, the cam engaging wheel ISI of each basket 34passes behind the inturned end I58 and along the straight portion of thecam member I67 to lift the cover member IE'I, as shown in Figure 5, soas to permit the carton to enter the basket 34. As the basket passesbeyond the cam I67, the cover is returned to its closed position, asshown in Figure 10, by the spring I M.

As seen in Figure 4, the cartons are discharged from the containers atas they pass along the straight stretch between idler pulleys 62 and thepair of pulleys 55 and 55 at the right-hand end of the figure. Thetransfer apparatus has not been shown in Figure 4, but is shown inFigure 12. As each basket 3 passes along this straight stretch, a fixedcam member IIfi, similar to cam I 6'5, engages the cam wheel IIiI,throwing the top closure member I5? to the open position or to the rear.This opening movement causes the downwardly extending portion I63 toclear the edge of the carton I G4 which drops into the transfercontainer I72. Means may be provided for mechanically ejecting thecartons from the baskets or they may be blown out by an air jet abovethe basket. One form of mechanical ejector has been shown on Figures 10,11 and 12 and comprises a pusher plate ISI inside the back wall II 9 ofthe basket t l to which is connected a push rod I92 having a head I93.The compression spring I94 encircles the push rod I92 between the bossI95. This spring I94 normally holds the plate ISII in contact with thewall I I9. When the cam I95, shown on Figure 12, engages the head I93,the rod I92 is pushed down and the plate IQI ejects the carton. The camI95 is coordinated with cam I'IIi which opens the basket 34".

This transfer basket I72 is one of a series supported by the continuouschain I'IS, the basket I12 being so spaced and the linear speed of thebasket I12 so related to the movement of the waxer chain conveyor that abasket I'IZ passes under each conveyor basket 34 at the proper instantto receive the carton when it is discharged from basket 34. Thecontinuous chain lit carrying members H2, like the Waxer chain conveyor,moves continuously. The chain I13 is provided, as shown, with an upperseries of rollers Ii i rotating in a fixed track IE5 and a lower seriesof rollers 5'55 rotating in the lower fixed track Ill.

The bottom 27:?- of each transfer basket H2 is pivoted at 533 and a camarm IBI carrying a cam roller 532 extends from each bottom. The conveyormoves around its guides and carries with it the members 72 with the camroller I82 rolling around on the rail Ill until member IIZ approachesthe vertical at the lower left of Figure 12. At this point, the camroller 532 strikes the sharp cam rise I3 1, swinging the parts to theposition shown in the lower portion of the figure. This causes thebottom I "E9 to swing inwardly and thrust the carton Md into the openpocket I carried by the cooler conveyor chain IBI. The spring 58%,connected to the end I 95. of the transfer container I'IZ and at itsother end to the pivoted bottom iii, of that container, serves to holdthe roller I32 against the cam rise IM and to return the bottom tonormal position as soon as the carton has been transferred to t1 epocket I85 and the roller its leaves the cam rise I8 1.

The baskets I12 are provided at their right end, as seen in Figure 12 atthe point where they receive the cartons from baskets 34, with a shortlip I96 to limit movement of the cartons in that direction.- The.baskets. I72 take a path having a horizontal upper run and conoidal endruns joining the lower vertical run from which the cartons aretransferred to the cooler pockets I35.

The heating coils IS? are shaped to be located adjacent the bottomwallsI73 of the baskets I12 during this travel, their configuration beingshown in Figure 13 as seen from the left of Figure 12. These coils I97are connected to coils I93 which, as shown in Figure 12, engage thebottom of the carton. The coils I 88 have an arcuate portion I99extending up around the major portion of the left curved end of coilI91, as shown in Figure 13, the coil I9? being bent so as to engage thebottom of the carton as it moves around in one of the baskets I'IZ.These heated coils I98 are not straight but are individually waved inparallel relation so that all portions of the bottom of the carton arewiped to ensure a smooth even layer of wax on the carton bottom as thecarton is delivered to the cooler.

The general layout of the control of the wax supply is shown in Figure3. The wax melting chamber 28!! is provided with a removable cover Zfiiand with electrically heated wax slab support bars tilt. The melted waxpasses downward through the bars and through the strainer 204 and flowsfrom the inclined surface 285 to the sump 2%. The sump 206 and all theimmediately adjacent piping are enclosed in a hot water bath 261 so asto prevent solidification of the wax and, also, to maintain thetemperature at that desired for coating purposes. This water jacket 25]!has a relatively narrow portion 2.88 below the sloping surface 265 andunder the sump 2216 and is enlarged to surround the filter 209 and thepiping leading to and from the filter. A connected water jacket 2H1surrounds the wax bath 243.

The centrifugal pump 2! I at the bottom of the sump 286 is driven by themotor 2E2 through the downwardly extending shaft 2 M. This pump 2Hpasses the molten wax through piping 2H6 in the sump and piping m in thewater jacket to the filter 269. The outlet pipe 2!! leads from theoutlet side or the filter and makes a right angle bend leading directlyinto the wax bath Z63 itself which is in the rear of the section shownin Figure 3, its bottom being indicated in broken lines at 2'44. Thispipe 2H is controlled by the rear valve shown in broken lines and havingthe upwardly extending valve handle 25%. This pipe 2 i? also leads topipe 2% which passes through valve 222 controlled by handle 223 to thelateral pipe 225. This pipe 225 extends upwardly at 22? to dischargeinto the trim or storage tank 229. This tank 229 is provided with aninsulated covering 21-55 and a water jacket 23 H.

An electrical water heater 232 is shown at the lower right of Figure 3,this supplying water at the desired temperature for circulation to thewater jackets around the wax bath, the sump and piping, the jacketaround the trim tank 22d and also to the coils is? and 193 shown inFigures l2 and 3. As shown in Figure the hot water jacket 2t?surrounding the sump 286 and the filter 2559 and related piping isenclosed in an insulating covering 233. The wa-x bath water jacket 255i,shown in Figure 4, is also enclosed by an insulating covering 23 3.While an electrical water heater has been shown in Figure 3, it will beunderstood that other means, such as steam pipes for example, may beused to heat the water for the water jackets. Also, the trim tank 223may be provided with immersion heating means such as steam coils orelectrically heated plates or coils, The motor 23% provides a pump tomaintain circulation, and the detailed piping and circulatory systemforms no part of the present invention and need not be described infurther detail. Suitable thermostatically controlled valves may beprovided to maintain the desired temperature and circulation. One suchthermostat is indicated at 238, a thermostatic control line 233 leadingto valve 2%.

The sump 2% is directly connected through passage 2 52 to the lowermostportion of the wax applying or carton dipping tank the outline of whichis indicated at 2% in broken lines in Figure 3. This opening is coveredby screen 248. The fioat 2% is connected by rod 255 to a control unit 2t? which controls the supply of heating current to the electric meltingbars 203. This float 2 55 and its connecting rod 246 may be 16 soadjusted relative to the control device 241 as to maintain the moltenwax at a desired level. It will be understood that the level of wax inthe sump 2436 will be the same as the level of wax in the waxing tank 2%since the two directly communicate through the passage Therefore, thecontrol device serves to maintain the level in the actual waxing tank atthe desired point. This level may be held at different points underdifferent operating conditions. For example, certain types of board usedin making cartons may require greater time of immersion than other typesof board. The board will also vary in thickness with the size of cartonsand the contents for which they are adapted. An additional feature whichmay require modification or" the level is change in speed of theapparatus. The waxing apparatus must be timed to register exactly withthe speed of the carton maker or other apparatus supplying cartons to bewaxed. This is essential, since the container 34 on a conveyor must beopposite the receiving opening at the exact instant when a carton isfed. It will be apparent that, if the conveyor is operated more slowly,the level of the molten wax in the bath must be lowered if the carton isto be immersed for the same length of time. Conversely, on speeding upthe waxer conveyor, the wax level must be raised. The automatic controlsmay be set to maintain the desired depth and may be readily adjusted todifierent speeds so that an apparatus is provided which is adapted tovariable speed operation throughout a substantial range.

The wax melting apparatus included in the chamber 2% may also beprovided with an automatic control to indicate when additional slabs ofwax should be supplied to the melting chamber. This may be athermostatic control operated by a rise in temperature of the bars 293when they are not covered with wax and wax is consequently not drawingoff heat as it is melted.

The cooler is shown in Figures 16 and 17. As clearly shown in Figure 17,the conveyor chain 28? carries the open-sided pockets or cartonconveying carriages I555 through a tortuous path. These pockets I arelarger than the cartons so that the cooling air has access to the sidesof the cartons and both the sides and bottoms of the pockets areperforated so as to permit the cool air to flow around the cartons.Portions of the conveyor chain i8? are located outside of the coolingchamber 25% in order to receive and discharge the cartons. The chamber256 is enclosed in the insulated housing 25!. The chain it"? is drivenby means of sprocket 252 which is adjustably secured to a hub onvertical drive shaft 25d by means of the screws 255 fitting througharcuate slots 2%. As shown in Figure 16, the shaft 254'. is driventhrough a gear 25'! which, in turn, is driven by chain 258 from ahorizontal driven shaft 260. It will be understood that the movement ofthe conveyor chain 58's must be synchronized with the movement of theconveyor and transfer apparatus in the waxer so that an open-sidedpocket 585 is in proper position to receive each carton 144 as it isejected from its transfer basket l H.

The conveyor chain i8! moves in a clockwise direction about sprocket252, passing about idler sprockets 252, 263, 2% and 285 within thecooling chamber 256. It passes out of that chamber through an opening at265 and around idler sprocket 263 to idler sprocket 269 from which it 11returns to the drive sprocket 252. The cartons are fed to the open-sidedpockets 535 as they pass along the run 270 of the cooler conveyorextending between idler sprocket 269 and drive sprocket 252. Acontinuous reversely bent guide member 272 is provided opposite theouter open face of the pockets 35 so as to retain the cartons in thepockets, extending around sprocket 252, to and around sprocket 262 andback to sprocket 253, terminating at 273 adjacent flange 274. Theupstanding circular flange 27! is carried by and rotates with sprocket263 and is closely adjacent the open side of the pockets I85 as theyround thatsprocket so that it functions to hold the cartons I iin thepockets. A gener- I ally U-shaped guide 2'55 extends from adjacentrotating flange 21% around sprocket 254 and back to a point adjacent acircular flange 276 carried by sprocket 255. In the construction shown,a straight guide 277! extends from circular flange 235 to a pointoutside the discharge openin 255. It will be understood that guide 2??may be extended adjacent the conveyor and pockets 535 to a pointadjacent-the location where it is desired to discharge the cartons fromthe pockets. It will be understood that the exact point of discharge ofthe cartons is immaterial and that they may be discharged at any pointafter they leave the interior of the cooling chamber 250, a defleetingspring or its equivalent ejecting means being located at the properpoint for transferring the cartons to another conveyor or to packagingor filling apparatus.

As shown in Figure 15, refrigerating apparatus 278 of any desired typeis contained in chamber 279 at the right end of the cooler assembly.This apparatus cools coils located in the path of the air. Air is drawnin through the lateral opening 289 in fan chamber 285 and discharged byfan 282 into the housing 233. In the housing 283 the air passes throughthe filter 28 From housing 293 the chilled air moves upwardly throughpassage 235. A plurality of deflecting vanes 255 are provided as the airturns upwardly to assist in guiding its change of direction. moves fromthe upwardly extending passage 285 into an upper horizontal passage 283.A short downwardly and rearwardly directed passage 298 leads from thelower portion of passage 238 adjacent its left end. The amount of airflowing n through passage 290 is controlled by slide 29!. The remainderof the air passes out of the lower face of passage 255 through openingscontrolled by the tiltahle deflecting doors 293 and 29% and downwardlyinto the chamber 259. downwardly directed passage 299 serves to direct ablast of chilled air downwardly into the open upper ends of the cartons1 3 i shortly after they enter the chamber 250 to thus quickly chill theinterior coating of the cartons. The main circulation of chilled air inthe chamber 259 serves to continue the cooling so that the wax coatinghas hardened sufiiciently for all practical handling and fillingpurposes by the time the The short 7 iii) cartons leave the chamber 250through the opening 266.

As best shown in Figure 17, the floor of chamher 259 is provided with aplurality of openings or ducts 2st through which the air passesdownwardly into fan chamber 28!, which chamber is entirely enclosed andcovered by insulation 291. All or a part of the ducts 296 are providedwith flow control means such, for example, as the tilting doors 298which may be variously adjusted in different ducts to control and directthe air flow as desired. The cool air is thus recirculated and isfiltered as it leaves the fan housing 283 to return to the coolingchamber 259 by way of passages 285 and 288.

While I have shown certain preferred embodiments of apparatus forcarrying out my invention, these are to be understood to be illustrativeonly as the method is capable of variation to meet I differingconditions and requirements, and 1 contemplate such modifications ascome within the spirit and scopeof the appended claims.

I claim:

1. The method of waxing cartons which comprises continuously supplyingcartons in single spaced relation, said cartons having an open top,lateral walls and a closed bottom, holding individual cartons and movingthe held cartons through a molten wax bath, draining the cartons ofexcess wax While maintaining them at a temperature to preventsolidification of the wax, moving the while their bottoms rest on aheated surface to smooth the wax on the carton bottom, transferring thecartons to a cooling zone, moving the cartons continuously through thecooling zone to solidify the wax and continuously discharging them fromsaid zone.

2. The method of waxing cartons having an open top, lateral walls and aclosed bottom, which comprises continuously supplying cartons in spacedseries, grasping the cartons individually and positively moving thegrasped cartons in a substantially rectilinear path through a bath ofmolten wax, the cartons entering the wax with a lateral wall at an acuteangle to the surface of the wax and the open end uppermost, tilting thecarton in the opposite direction to bring the open end lowermost anddraining the cartons of excess wax, releasing the positive grasptransferring the cartons to individual carton supporting means,smoothing portions of the coated surface of each carton by means of theapplication of heated means, and thereafter conveying the cartons inindividual spaced relation through a cooling zone.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 1,461,760 Morinsky July 17, 1923 1,480,790 Stanley Jan. 15,19% 1,594,991 Barlow Aug. 3, 1926 1,874,568 Melville et al Aug. 30, 19321,967,856 Beckman July 24, 1934 2,189,738 Miller Feb. 6, 1940

1. THE METHOD OF WAXING CARTONS WHICH COMPRISES CONTINUOUSLY SUPPLYING CARTONS IN SINGLE SPACED RELATION, SAID CARTONS HVING AN OPEN TOP, LATERAL WALLS AND A CLOSED BOTTOM, HOLDING INDIVIDUAL CARTONS AND MOVING THE HELD CARTONS THROUGH A MOLTEN WAX BATH, DRAINING THE CARTONS OF EXCESS WAX WHILE MAINTAINING THEM AT A TEMPERATURE TO PREVENT SOLIDIFICATION OF THE WAX, MOVING THE CARTONS WHILE THEIR BOTTOMS REST ON A HEATED SURFACE TO SMOOTH THE WAX ON THE CARTON BOTTOM, TRANSFERRING THE CARTONS TO A COOLING ZONE, MOVING THE CARTONS CONTINUOUSLY THROUGH THE COOLING ZONE TO SOLIDIFY THE WAX AND CONTINUOUSLY DISCHARGING THEM FROM SAID ZONE. 